Catheter including a bendable portion

ABSTRACT

An endoscope system having an endoscope, an external tube associated with said endoscope and extending alongside said endoscope, an endoscope tool extending through said external tube and having formed along at least part of an elongate surface thereof a hydrophilic coating; and a liquid communication port associated with said external tube for providing liquid communication with the interior of said external tube.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 13/343,029, filed Jan. 4, 2012, which is acontinuation application of U.S. patent application Ser. No. 12/600,838,which is a U.S. National Phase Application under 35 U.S.C. 371 of PCTInternational Application No. PCT/IL2008/000687, which has aninternational filing date of May 20, 2008. Reference is made to thefollowing related applications, the disclosures of which are herebyincorporated by reference and priority of which is hereby claimedpursuant to 35 U.S.C. 37 CFR 1.78(a) (4) and (5)(i):

PCT Application No. PCT/IL2007/000600, filed May 17, 2007; U.S.Provisional Patent Application Ser. No. 60/924,578, filed May 21, 2007,entitled BALLOON CATHETER WITH UNIQUE GUIDEWIRE ASSEMBLY;

U.S. Provisional Patent Application Ser. No. 61/064,707, filed Mar. 21,2008, entitled EXTERNAL CHANNEL FOR ELONGATED MEDICAL INSTRUMENTS; and

U.S. Provisional Patent Application Ser. No. 61/064,735, filed Mar. 24,2008, entitled BALLOON ASSEMBLY FOR ENDOSCOPY.

Reference is also made to applicant's copending PCT Application No.PCT/IL2005/000152, filed Feb. 7, 2005; and PCT Application No.PCT/IL2005/000849, filed Aug. 8, 2005, the disclosures of which arehereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to catheters generally.

BACKGROUND OF THE INVENTION

The following patent publications are believed to represent the currentstate of the art:

U.S. Pat. No. 7,169,105 and 7,056,284.

SUMMARY OF THE INVENTION

The present invention seeks to provide an improved catheter. The term“catheter” is used to define a medical device including a hollow tubewhich may be passed into a body for investigation and/or treatment.

There is thus provided in accordance with a preferred embodiment of thepresent invention a catheter including a tube having at least one lumen,at least one elongate element, the at least one elongate element havinga bendable portion at a predetermined bendable portion locationtherealong forward of a distal end of the tube and at least oneselectably inflatable balloon communicating with at least one of the atleast one lumen, the at least one selectably inflatable balloon having aforward end and a rearward end, the rearward end of the balloon beinglocated rearwardly of the predetermined bendable portion location.

Preferably, the forward end of the balloon is located rearwardly of thepredetermined bendable portion location. Alternatively, the forward endof the balloon is located forwardly of the predetermined bendableportion location.

In accordance with a preferred embodiment of the present invention thecatheter also includes a steering element coupled to the elongateelement forwardly of the predetermined bendable portion location.Additionally, the steering element is manipulatable by an operator forsteering of the catheter. Additionally or alternatively, the steeringelement is operative to apply a pulling force to a distal portion of theelongate element.

Preferably, the pulling force causes the distal portion to rotaterelative to a longitudinal axis of the catheter. Additionally, the atleast one elongate element is resilient and returns to its axialorientation when the pulling force is no longer applied thereto.

In accordance with a preferred embodiment of the present invention adiameter of the balloon when fully inflated is in the range of 35-45 mm.

There is also provided in accordance with another preferred embodimentof the present invention a catheter including a tube having at least onelumen and having a bendable portion at a predetermined bendable portionlocation therealong and at least one selectably inflatable ballooncommunicating with at least one of the at least one lumen, the at leastone selectably inflatable balloon having a forward end and a rearwardend, the rearward end of the balloon being located rearwardly of thepredetermined bendable portion location.

Preferably, the forward end of the balloon is located rearwardly of thepredetermined bendable portion location. Alternatively, the forward endof the balloon is located forwardly of the predetermined bendableportion location.

In accordance with a preferred embodiment of the present invention thecatheter also includes a steering element coupled to the tube forwardlyof the predetermined bendable portion location. Additionally, thesteering element is manipulatable by an operator for steering of thecatheter. Additionally or alternatively, the steering element isoperative to apply a pulling force to a distal portion of the tube.

Preferably, the pulling force causes the distal portion to rotaterelative to a longitudinal axis of the catheter. Additionally, the tubeis resilient and returns to its axial orientation when the pulling forceis no longer applied thereto.

In accordance with a preferred embodiment of the present invention adiameter of the balloon when fully inflated is in the range of 35-45 mm.

There is further provided in accordance with yet another preferredembodiment of the present invention a catheter including a tube havingat least one lumen, at least one elongate element, at least part ofwhich is extendable forwardly of a distal end of the tube to a fixedorientation at which a distal end of the at least one elongate elementextends beyond the distal end of the tube by a fixed amount and at leastone selectably inflatable balloon communicating with at least one of theat least one lumen, the at least one selectably inflatable balloonhaving a forward end and a rearward end, the rearward end of the balloonbeing located adjacent the distal end of the tube at a rearward balloonend mounting location and the forward end of the balloon being locatedadjacent a distal end of the at least one elongate element at a forwardballoon end mounting location, wherein the balloon is configured suchthat when the at least one elongate element is in the fixed orientationand the balloon is in a deflated operative orientation, the distancebetween the rearward balloon end mounting location and the forwardballoon end mounting location is greater than the distance between therearward balloon end mounting location and the forward balloon endmounting location when the balloon is an inflated operative orientation,thereby producing bowing of the at least one elongate element uponinflation of the balloon.

Preferably, the distance between the rearward balloon end mountinglocation and the forward balloon end mounting location is greater thanthe distance between the rearward balloon end mounting location and theforward balloon end mounting location when the balloon is an inflatedoperative orientation by at least 20%. Additionally or alternatively,the bowing of the elongate element is in a predetermined direction.Alternatively or additionally, the bowing of the elongate elementproduces an asymmetric, inflated balloon configuration.

There is even further provided in accordance with still anotherpreferred embodiment of the present invention a catheter including atube having at least one lumen and at least one selectably inflatableasymmetrical balloon communicating with at least one of the at least onelumen, the at least one selectably inflatable asymmetrical balloonhaving a forward end and a rearward end, the balloon, when not inflated,having a generally tapered forward facing portion having increasingdiameter from the forward end toward the rearward end and a generallytapered rearward facing portion having decreasing diameter from theforward end toward the rearward end, the extent of tapering of theforward and rearward facing portions being different.

Preferably, the extent of tapering of the forward portion is less thanthe extent of tapering of the rearward portion.

There is also provided in accordance with another preferred embodimentof the present invention an endoscope system including an endoscope, anexternal tube associated with the endoscope and extending alongside theendoscope; an endoscope tool extending through the external tube andhaving formed along at least part of an elongate surface thereof ahydrophilic coating and a liquid communication port associated with theexternal tube for providing liquid communication with the interior ofthe external tube.

There is further provided in accordance with yet another preferredembodiment of the present invention for use with an endoscope, anexternal tube assembly including an external tube associated with theendoscope and extending alongside the endo scope, an endoscope toolextending through the external tube and having formed along at leastpart of an elongate surface thereof a hydrophilic coating and a liquidcommunication port associated with the external tube for providingliquid communication with the interior of the external tube.

There is even further provided in accordance with still anotherpreferred embodiment of the present invention an endoscope systemincluding an endoscope, an external tube associated with the endoscopeand extending alongside the endoscope and a drainage vessel associatedwith the external tube for receiving liquid from the interior of theexternal tube.

There is also further provided in accordance with a further preferredembodiment of the present invention for use with an endoscope, anexternal tube assembly including an external tube associated with theendoscope and extending alongside the endoscope and a drainage vesselassociated with the external tube for receiving liquid from the interiorof the external tube.

There is further provided in accordance with another preferredembodiment of the present invention an enhanced flexibility auxiliaryendoscope assembly for use with an endoscope, the assembly including atleast one flexible elongate element, a flexible sleeve having a firstlumen for accommodating a distal portion of an endoscope and a secondlumen for accommodating the at least one flexible elongate element andan inflatable balloon mounted onto the flexible sleeve, the inflatableballoon, when in a non-inflated state, having a forwardly facinggenerally tapered end and a rearwardly facing generally tapered end, theforwardly facing generally tapered end having a slope which is lesssteep than a corresponding slope of the rearwardly facing generallytapered end.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be understood and appreciated more fully fromthe following detailed description, taken in conjunction with thedrawings in which:

FIGS. 1A and 1B are, respectively, pictorial and exploded viewsimplified illustrations of a flexible endoscope system constructed andoperative in accordance with a preferred embodiment of the presentinvention;

FIGS. 2A and 2B are respective exploded and partially cut-away pictorialillustrations of a catheter or endoscope tool and associated inflationtube, constructed and operative in accordance with a preferredembodiment of the present invention;

FIGS. 3A and 3B are sectional illustrations of the catheter or endoscopetool of FIGS. 2A & 2B in respective straight and bent operative steeringorientations;

FIGS. 4A and 4B are respective exploded and partially cut-away pictorialillustrations of a catheter or endoscope tool and associated inflationtube, constructed and operative in accordance with another preferredembodiment of the present invention;

FIGS. 5A and 5B are sectional illustrations of the catheter or endoscopetool of FIGS. 4A & 4B in respective straight and bent operative steeringorientations;

FIGS. 6A, 6B and 6C are simplified schematic illustrations of aninflation control unit forming part of the flexible endoscope system ofFIGS. 1A and 1B in three different operative orientations;

FIGS. 7A, 7B, 7C and 7D are simplified flow charts illustratingpreferred modes of operation of the inflation control unit of FIGS.6A-6C;

FIGS. 8A and 8B are simplified partially cut away illustrations of aballoon catheter constructed and operative in accordance with apreferred embodiment of the present invention;

FIGS. 9A, 9B, 9C, 9D, 9E and 9F are simplified, partially cut away,partially sectional, illustrations of the operation of the apparatus ofFIGS. 8A and 8B;

FIGS. 10A and 10B are simplified, partially cut away, partiallysectional, illustrations of a balloon catheter/external tube assemblyconstructed and operative in accordance with a preferred embodiment ofthe present invention;

FIGS. 11A, 11B, 11C, 11D, 11E & 11F are simplified, partially cut away,partially sectional, illustrations of the operation of the apparatus ofFIGS. 10A and 10B;

FIG. 12 is a simplified illustration of a flexible endoscope systemsimilar to that shown in FIGS. 1A and 1B;

FIGS. 13A and 13B are simplified partially cut away illustrations ofportions of the system of FIG. 12;

FIGS. 14A, 14B, 14C & 14D are simplified, partially cut away, partiallysectional, illustrations of the operation of an endoscope tool as shownand described hereinabove with reference to FIGS. 2A-3B, including aballoon catheter as shown and described hereinabove with reference toFIGS. 8A & 8B, together with an endoscope, such as that shown anddescribed hereinabove with reference to FIGS. 9B-9F;

FIGS. 15A and 15B are respective exploded and partially cut-awaypictorial illustrations of a catheter or endoscope tool and associatedinflation tube, constructed and operative in accordance with anotherpreferred embodiment of the present invention;

FIGS. 16A and 16B are sectional illustrations of the catheter orendoscope tool of FIGS. 15A & 15B in respective straight and bentoperative steering orientations; and

FIGS. 17A and 17B are simplified illustrations of a portion of analternative embodiment of the flexible endoscope system of FIGS. 1A and1B.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The terms “endoscope” and “endoscopy” are used throughout in a mannersomewhat broader than their customary meaning and refer to apparatus andmethods which operate within body cavities, passageways and the like,such as, for example, the small intestine, the large intestine, arteriesand veins. Although these terms normally refer to visual inspection, asused herein they are not limited to applications which employ visualinspection and refer as well to apparatus, systems and methods whichneed not necessarily involve visual inspection.

The term “distal” refers to the remote end of an endoscope, accessory ortool furthest from the operator.

The term “proximal” refers to the end portion of an endoscope, accessoryor tool closest to the operator, typically outside an organ or bodyportion of interest.

Reference is now made to FIGS. 1A & 1B, which illustrate an endoscopysystem 100 constructed and operative in accordance with a preferredembodiment of the present invention. The endoscopy system 100 preferablyincludes a console 102, such as a console including a EPK-1000 videoprocessor and a SONY LMD-2140MD medical grade flat panel LCD monitor,all commercially available from Pentx Europe GmbH, 104 Julius-VosselerSt., 22527 Hamburg, Germany. The system 100 preferably includes aconventional flexible endoscope 104, such as a VSB-3430K videoenteroscope or a EC-3470LK video colonoscope which are commerciallyavailable from Pentx Europe GmbH, 104 Julius-Vosseler St., 22527Hamburg, Germany.

In accordance with a preferred embodiment of the invention, an auxiliaryendoscopy assembly 106 comprising a peripheral balloon 108 may bemounted onto endoscope 104 as shown, by means of a tubular sleeve 110having a central lumen 111 which is placed over part of the distalportion of endoscope 104, and is associated with peripheral balloon 108.Many of the features of auxiliary endoscopy assembly 106 are describedin one or more of applicant/assignee's PCT Application No.PCT/IL2005/000152, filed Feb. 7, 2005; PCT Application No.PCT/IL2005/000849, filed Aug. 8, 2005, and PCT Application No.PCT/IL2007/000600, filed May 17, 2007, the disclosures of which arehereby incorporated by reference.

It is appreciated that the tubular sleeve 110 may be constructed of aflexible and stretchable material, such as flexible and stretchablesilicon, latex or rubber, thereby enabling it to conform with bending ofendoscope 104. It is further appreciated that tubular sleeve 110preferably has an untensioned inner circumference slightly larger thanthe cross-sectional circumference of endoscope 104, thereby allowing itto be pulled and slid over the endoscope 104.

As illustrated in FIGS. 1A & 1B, peripheral balloon 108 at leastpartially overlays tubular sleeve 110 at a location adjacent a distalend of tubular sleeve 110, and is fixed thereon at both edges by anysuitable conventional means, such as an adhesive, in order to define asealed volume therebetween. Preferably, inflation and deflation ofperipheral balloon 108 is provided via a lumen 112, which preferably isdefined by tubular sleeve 110 and communicates with the interior ofperipheral balloon 108 via at least one aperture 114. Lumen 112preferably communicates with an inflation control assembly 115 via atube 116. Inflation control assembly 115 preferably comprises a controlunit 117 having associated therewith dual foot pedals 118 and anoperational status indicator panel 119.

Tube 116 may be attached to endoscope 104 at multiple locations alongits length by any suitable conventional means such as medical adhesivetape or flexible bands 120.

It is appreciated that in accordance with a preferred embodiment of thepresent invention peripheral balloon 108 is generally inflatable, andcan be inflated to a diameter about 3-10 times larger than its diameterwhen not inflated. In accordance with a preferred embodiment of thepresent invention, useful for small intestine endoscopy, the diameter ofperipheral balloon 108 when fully inflated is in the range of 35-45 mm.Preferably, inflation of the peripheral balloon 108 to a diameter lessthan 45 mm may be achieved using relatively low pressure, such as in therange of 30-70 millibars.

In another specific embodiment, useful for large intestine endoscopy,the diameter of the peripheral balloon, when fully inflated, is in therange of 4-6 centimeters. In a further embodiment, also useful for largeintestine endoscopy, the diameter of the peripheral balloon, when fullyinflated, is six centimeters. Preferably, inflation of the peripheralballoon 108 to a diameter less than six centimeters may be achievedusing relatively low pressure, such as in the range of 30-70 millibars.

It is appreciated that in accordance with a preferred embodiment of thepresent invention, useful for in vivo inspection of a generally tubularbody portion having a variable cross-sectional diameter, the expansiondiameter range of peripheral balloon 108 is larger than the maximumcross-sectional diameter of the generally tubular body portion, therebyenabling engagement of expanded peripheral balloon 108 with the interiorsurface of the generally tubular body portion, and anchoring of theendoscope 104 thereto. Preferably, peripheral balloon 108 is arelatively soft, highly compliant balloon, operative to at leastpartially conform to the shape of the interior surface of the generallytubular body portion when in engagement therewith.

It is appreciated that peripheral balloon 108 may be formed of suitablewell-known stretchable materials such as latex, flexible silicon, orhighly flexible nylon. Alternatively, peripheral balloon 108 may beformed of polyurethane, which is less stretchable and conforming thanlatex, flexible silicon or highly flexible nylon. Preferably, thediameter of peripheral balloon 108 is sufficient to ensure tightanchoring at any part of the generally tubular body portion.Alternatively, peripheral balloon 108 may be obviated.

In accordance with one embodiment of the present invention, tubularsleeve 110 and peripheral balloon 108 may be produced from differentmaterials. For example, sleeve 110 may be formed of very thin and veryflexible polyurethane while balloon 108 is formed of nylon.Alternatively, sleeve 110 and balloon 108 may be produced from generallythe same material but with different mechanical properties. For example,balloon 108 may be formed of a silicon material having width of 0.5millimeter and hardness of approximately 50 shore D, whereas sleeve 110may be formed of a silicone material having width of 0.3 millimeter andhardness of approximately 30 shore D. A preferred structure of sleeve110 provides high bendability of the distal portion of endoscope 104together with tubular sleeve 110. A preferred structure of balloon 108provides firm anchoring of endoscope 104 to the generally tubular bodyportion when balloon 108 is in an inflated state.

In a preferred embodiment of the present invention, auxiliary assembly106 may comprise at least one external tube 122. External tube 122 maybe attached to the endoscope 104 at multiple locations along its lengthby any suitable conventional means such as medical adhesive tape orflexible bands 120. External tube 122 is preferably attached to tube 116by a band 123. A proximal end 124 of tube 122 is typically open toenable a proximal end 125 of an inflation tube 126 coupled to a balloon127 of an endoscope tool 128 to extend therefrom outside of a patient'sbody, thereby enabling insertion, removal and manipulation of tool 128by an operator. Additionally any other suitable endoscope tool may beinserted, removed or manipulated through tube 122. Proximal end 125 ofinflation tube 126 of endoscope tool 128 is also coupled to theinflation control assembly 115.

Many of the features of endoscope tool 128 are described in one or moreof applicant/assignee's PCT Application No. PCT/IL2005/000152, filedFeb. 7, 2005; PCT Application No. PCT/IL2005/000849, filed Aug. 8, 2005,and PCT Application No. PCT/IL2007/000600, filed May 17, 2007, thedisclosures of which are hereby incorporated by reference.

In accordance with a preferred embodiment of the present invention,useful for small intestine endoscopy, the diameter of balloon 127 whenfully inflated is in the range of 35-45 mm. Preferably, inflation of theperipheral balloon 127 to a diameter less than 45 mm may be achievedusing relatively low pressure, such as in the range of 30-70 millibars.

A distal end 129 of external tube 122 preferably extends slidably andtelescopically through part of the length of a coil spring 130 whichmovably and slidably resides within a lumen 132, which preferably formspart of tubular sleeve 110. Preferably distal end 129 is beveled forease of passage into and through coil spring 130. It is a particularfeature of the present invention that spring 130 defines a generallynon-collapsible and highly flexible channel for endoscope tool 128. Itis a further particular feature of the present invention that lumen 132has a generally saddle shaped cross section, as seen particularly atreference numeral 134, which is sufficiently wide to enable spring 130to be slidably displaced laterally depending on the curvature of theendoscope 104. This enhances the flexibility of the combination ofendoscope 104 and the auxiliary assembly 106. It is appreciated thatalthough provision of spring 130 is preferred, spring 130 may bereplaced by a suitable, flexible, non-collapsible tube of another type.In accordance with a preferred embodiment of the present invention,useful for small intestine endoscopy, the inner diameter of spring 130is in the range of 3-6 mm. Preferably, balloon 127 when in a fullydeflated state may assume a small enough cross section to allow itspositioning at least partially within spring 130 if needed, for exampleduring oral insertion of the flexible endoscope assembly through thestomach into the small intestine.

As illustrated in FIG. 1A, a distal end 136 of spring 130 is locatedadjacent to a first side wall 137 of lumen 132. Spring 130 extendsgenerally diagonally along lumen 132 such that a proximal end 138thereof lies adjacent a second side wall 139 of lumen 132, opposite tofirst side wall 137.

It is appreciated that during operation of the endoscopy system 100,when the endoscope 104 and the auxiliary endoscopy assembly 106 arecurved in various directions, the orientation of spring 130,particularly proximal end 138 thereof, may change appropriately.

It is seen that spring 130 is preferably angularly misaligned with arespect to the central lumen 111. Generally diagonal orientation ofspring 130 within lumen 132 is particularly useful in reducing,minimizing or eliminating substantial resistance of spring 130 tobending of endoscope 104 inserted within central lumen 111.

A forward collar element 140 preferably receives distal end 136 of coilspring 130 and removably connects it to a distal end 142 of tubularsleeve 110 and thus to a distal end 144 of endoscope 104 in press-fitfrictional engagement. A stretchable band 146 preferably surroundscollar element 140 and presses it into frictional engagement with distalend 142 of tubular sleeve 110 and with distal end 144 of endoscope 104.It is appreciated that lumens 112 and 132 do not extend to distal end142 of tubular sleeve 110 and thus are not engaged by collar element140.

It is appreciated that the lumens 111, 112 and 132 may be formedintegrally as part of tubular sleeve 110 in any appropriate manner, suchas by extrusion, for example. Alternatively, any one or more of lumens111, 112 and 132 may be formed as a separate tube and may be attached totubular sleeve 110 in any suitable manner, such as by an adhesive.

In a preferred embodiment of the present invention, tubular sleeve 110is approximately 120-200 mm in length and spring 130 is approximately100-160 mm in length.

Preferably, the longitudinal distance between a distal edge ofperipheral balloon 108 and the distal edge of tubular sleeve 110 doesnot exceed approximately 20 mm.

It is a particular feature of the present invention that a typical wallthickness of lumens 111, 112 and 132 of the tubular sleeve 110 isrelatively thin, such as in the range of 0.15-0.7 mm, so as to provideenhanced flexibility of the tubular sleeve 110.

Preferably, for a typical endoscope diameter range of 10-13 mm, thecircumference of central lumen 111 is preferably in the range of 31-41mm, and its inner diameter is preferably 1-3 mm larger than the outerdiameter of the endoscope.

In accordance with a preferred embodiment of the invention, inflationtube 126 includes a guide wire 150, which is preferably selectablybendable at one or more predetermined bending locations, here indicatedin phantom lines by indentations 152. Guide wire 150 preferablyterminates adjacent a distal end of balloon 127. Further in accordancewith a preferred embodiment of the present invention, inflation tube 126also includes a selectable steering wire 154, which extends beyond theproximal end of inflation tube 126, so as to be manipulatable by anoperator for steering of the endoscope tool 128.

A distal end of selectable steering wire 154 is fixedly coupled to theguide wire 150 at an attachment location forwardly of one or morepredetermined bending locations. The attachment location may be eitherinterior of balloon 127 or forward thereof. Pulling on the selectablesteering wire 154 causes bending of the guide wire 150 and correspondingsteering of the endoscope tool 128.

It is appreciated that the structure of the inflation tube 126,including guide wire 150 and selectable steering wire 154, and thecorresponding structure of the endoscope tool 128, although illustratedand described herein as an endoscope tool structure, is equallyapplicable to catheters generally, which may be employed without anendoscope.

Reference is now made to FIGS. 2A and 2B, which are respective explodedand partially cut-away pictorial illustrations of a catheter orendoscope tool 128 and associated inflation tube 126 constructed andoperative in accordance with a preferred embodiment of the presentinvention. As seen in FIGS. 2A & 2B, the inflation tube 126 terminatesat a cap 156, which is attached at the interior of a distal end ofinflation tube 126 and preferably includes at least two lumens, heredesignated by reference numerals 158 and 160. The guide wire 150preferably extends through lumen 158 and is fixed to cap 156 thereat,while the selectable steering wire 154 preferably extends through lumen160.

A collar 166 preferably fixedly attaches a distal end of selectablesteering wire 154 to the guide wire 150 forwardly of at least oneindentation 152. In this embodiment, the attachment location, designatedby reference numeral 168, of the distal end of the selectable steeringwire 154 to the guide wire 150 by collar 166 lies within balloon 127.

A distal end of the guide wire 150 preferably is fixed to a tip element170, preferably within a recess 172 formed therein. Balloon 127 issealingly fixed, at a proximal end thereof, onto a distal end ofinflation tube 126 and, at a distal end thereof, onto a proximal end oftip 170.

Reference is now made to FIGS. 3A & 3B, which are sectionalillustrations of the catheter or endoscope tool of FIGS. 2A & 2B inrespective straight and bent operative steering orientations. FIG. 3Ashows the catheter or endoscope tool extending along a longitudinal axis174. It is seen that when selectable steering wire 154 is retractedrelative to cap 156, as indicated by arrow 176, it applies a pullingforce to a distal portion 178 to the guide wire 150 forward ofindentation 152, causing distal portion 178 and tip element 170 torotate in a direction indicated by arrow 180 relative to longitudinalaxis 174. Preferably the guide wire 150 is sufficiently resilient undersuch bending so as to return to its axial orientation shown in FIG. 3Aonce selectable steering wire 154 is released.

It is appreciated that torque may be applied to tube 126 and/or guidewire 150, thereby allowing an operator to rotate balloon 127 with tipelement 170 around axis 174 during in vivo inspection of a tubular bodyportion, such as described in one or more of applicant/assignee's PCTApplication No. PCT/IL2005/000152, filed Feb. 7, 2005; PCT ApplicationNo. PCT/IL2005/000849, filed Aug. 8, 2005, and PCT Application No.PCT/IL2007/000600, filed May 17, 2007, the disclosures of which arehereby incorporated by reference.

Reference is now made to FIGS. 4A and 4B, which are respective explodedand partially cut-away pictorial illustrations of a catheter orendoscope tool 128 and associated inflation tube 126 constructed andoperative in accordance with another preferred embodiment of the presentinvention. As seen in FIGS. 4A & 4B, the inflation tube 126 terminatesat a cap 186, which is attached at the interior of a distal end ofinflation tube 126 and preferably includes at least two lumens, heredesignated by reference numerals 188 and 190. The guide wire 150preferably extends through lumen 188 and is fixed to cap 186 thereat,while the selectable steering wire 154 preferably extends through lumen190.

A distal end 192 of selectable steering wire 154 is attached to a distalend 194 of guide wire 150 forwardly of at least one indentation 196,which here is located forwardly of balloon 127 in a recess 198 formed ina tip element 200. In this embodiment, the attachment of the distal end192 of selectable steering wire 154 to the distal end 194 of guide wire150 is realized by fixedly attaching distal ends 192 and 194 to the tipelement 200, within respective recesses 202 and 204, and the attachmentlocation, designated by reference numeral 206, lies within tip element200. Balloon 127 is sealingly fixed, at a proximal end thereof, onto adistal end of inflation tube 126 and, at a distal end thereof, onto aproximal end of tip 200.

Reference is now made to FIGS. 5A & 5B, which are sectionalillustrations of the catheter or endoscope tool of FIGS. 4A & 4B inrespective straight and bent operative steering orientations. FIG. 5Ashows the catheter or endoscope tool extending along a longitudinal axis210. As seen in FIG. 5B, when selectable steering wire 154 is retractedrelative to cap 186, as indicated by arrow 212, it applies a pullingforce to distal end 194 of the guide wire 150 forward of indentation196, causing distal portion 194 and tip element 200 to rotate in adirection, indicated by arrow 214, relative to longitudinal axis 210.Preferably, the guide wire 150 is sufficiently resilient under suchbending so as to return to its axial orientation shown in FIG. 5A onceselectable steering wire 154 is released.

It is appreciated that torque may be applied to tube 126 and/or guidewire 150, thereby allowing an operator to rotate balloon 127 with tipelement 200 around axis 210 during in vivo inspection of a tubular bodyportion, such as described in one or more of applicant/assignee's PCTApplication No. PCT/IL2005/000152, filed Feb. 7, 2005; PCT ApplicationNo. PCT/IL2005/000849, filed Aug. 8, 2005, and PCT Application No.PCT/IL2007/000600, filed May 17, 2007, the disclosures of which arehereby incorporated by reference.

Reference is now made to FIGS. 6A, 6B and 6C, which are simplifiedschematic illustrations of control unit 117 of inflation controlassembly 115 of the flexible endoscope system of FIGS. 1A and 1B inthree different operative orientations.

In a preferred embodiment of the present invention, the inflationcontrol assembly 115 is constructed and operative to facilitate thepneumatic inflation and/or deflation of balloons 108 and 127, which arecoupled thereto by respective tubes 116 and 126.

Control unit 117 of inflation control assembly 115 is preferably anelectro-mechanically operative pneumatic control subassembly whichincludes on its front panel a power on/off switch 312, connectors 313and 314, for respective tubes 116 and 126, preferably female-typepneumatic connectors, and a buzzer mute switch 316.

FIGS. 6A-6C each also illustrate a foot pedal electrical connector 318,an indicator panel electrical connector 320, and a power supplyelectrical connector 322, all of which are preferably female-typeelectrical connectors.

Specific reference is now made to FIG. 6A, which is a simplifiedschematic illustration of the control unit 117 in an ambient inflationpressure operational state. As seen in FIG. 6A, the control unit 117includes, in addition to the various connectors and switches describedhereinabove, an electronic controller 323, a buzzer 324, and twoidentical inflator/deflator assemblies, respectively indicated byreference numerals 326 and 328. The electronic controller 323 is anelectronic circuit which includes software that receives inputs fromvarious components of the inflation control assembly 115 and activatesvarious components of the inflation control assembly 115 in a mannerwhich is described hereinbelow with reference to FIGS. 7A-7D.

Inflator/deflator assemblies 326 and 328 each include a variable volumeair reservoir 334 which is coupled in a closed circuit with acorresponding balloon 108 or 127 via a corresponding tube 116 or 126. Apiston 336 is movable within each air reservoir 334 to thereby vary theair volume 337 of the air reservoir 334. Associated with each piston 336is a flange 338 arranged such that, during the axial movement of piston336, flange 338 may be located adjacent a deflated balloon status sensor340, an ambient balloon status sensor 342 and an inflated balloon statussensor 344. Each of sensors 340, 342 and 344 detects the proximity offlange 338 and provides a corresponding output to controller 323,indicating the corresponding volume of the air volume 337 and thus theinflation/deflation status of a corresponding balloon. Sensors 340, 342and 344 may be any suitable type of proximity sensors, such as opticalsensors or capacitive sensors. An example of an appropriate sensor typeis EE-SX672R, manufactured by Omron of Japan.

Piston 336 is driven linearly by a motor 346 moved inwardly or outwardlyof air reservoir 334, thereby respectively decreasing or increasing theair volume 337. The operation of motor 346 is controlled by controller323. Motor 346 may be any suitable electric motor, such as a linearmotor, a rotary motor or a step motor.

A mechanical stop 348 prevents the movement of piston 336 beyond apredefined distance, by physically engaging flange 338. This limitationprovides a limit on the pressure within air reservoir 334, due to thelimited decrease of the air volume 337 in air reservoir 334.

Air reservoir 334 is pneumatically connected, via a first intermediateair tube 350, to a valve 352 that has two states. An example of asuitable purging valve 352 is a solenoid valve G80-24V/DC 6.5W TWO WAYNO 1.6 mm, manufactured by Baccara of Israel. When the valve 352 is afirst state, it allows air flow via first intermediate air tube 350between air reservoir 334 and the ambient atmosphere. When 352 is in asecond state, air flowing via the first intermediate air tube 350communicates via valve 352, a balloon valve 354, and a secondintermediate air tube 356 with a corresponding balloon 108 or 127 (FIGS.1A & 1B).

Balloon valve 354 is typically a solenoid valve G80-24V/DC 6.5W TWO WAYNO 1.6 mm, manufactured by Baccara of Israel. Balloon valve 354 may bein either one of two states; an open state and a closed state. When theballoon valve 354 is in the open state, air flowing in secondintermediate air tube 356 can pass via the balloon valve 354 to a thirdintermediate air tube 358. When balloon valve 354 is open, thirdintermediate air tube 358 couples air from second intermediate air tube356 via balloon valve 354 to a pressure sensor 360.

Pressure sensor 360 detects the air pressure in the third intermediateair tube 358. The output of pressure sensor 360 may be used bycontroller 323 to govern the operation of the valve 352 and of theballoon valve 354. An example of pressure sensor 360 is sensor number6763, manufactured by Hegra Electric Ltd, Northern Way, Bury St.Edmunds, Suffolk IP32 6NN, United Kingdom.

It is appreciated that the output of pressure sensor 360 may be employedby the controller 323 for actuation of balloon valve 354, valve 352 andpiston 336. It is appreciated that actuation of the above describedpneumatic components may be different for different levels of pressureor vacuum which are indicated by pressure sensor 360. It is appreciatedthat pressure sensor 360 may comprise multiple pressure sensors, each ofwhich may provide a digital input of a single pressure value. Forinstance, detection of pressure higher than 60 mbar by pressure sensor360 may cause balloon valve 354 to be in its closed state. Detection ofpressure that is below 60 mbar by the pressure sensor 360 may causeballoon valve 354 to be in its open state. Similarly, detection of avacuum level lower than −100 mbar by pressure sensor 360 may cause theballoon valve 354 to be in its closed state.

A fourth intermediate air tube 362 allows air flow from air tube 358 viapressure sensor 360 to an overpressure release valve 364. Release valve364 has two states, an open and a closed state. In the closed state,release valve 364 allows air flow from fourth intermediate air tube 362to a fifth intermediate air tube 366. In the open state, release valve364 directs the air flow from fourth intermediate air tube 362 to theambient atmosphere. Release valve 364 is in its closed state as long asthe pressure within air tube 362 is below a predefined value. Wheneverthe pressure in air tube 362 exceeds the predefined value, the releasevalve 364 is automatically shifted to its open state.

This ensures that the pressure in a fifth intermediate air tube 366 andany components connected thereto outside of the control unit 117 (FIG.1A), does not exceed the predefined pressure value set for release valve364, corresponding to a safe, predefined value, such as 120 mbar. Thetransition of the release valve 364 from its closed to its open statemay be automatic as in release valve 559B-1M-1.0 psi, manufactured byCircle Seal Controls, Inc., 2301 Wardlow Circle, Corona, Calif. 92880,USA.

It is appreciated that the release valve 364 may also be controlled by abackup control mechanism.

Each intermediate air tube 366 is connected to a corresponding one oftubes 116 and 126 (FIG. 1A) via a corresponding one of connectors 313and 314.

It is appreciated that inflator/deflator assemblies 326 and 328 can beoperated using identical components and by implementing the same ordifferent algorithms, such that, for example balloon 108 may operate ata maximum inflation of 60 mbar, while balloon 127 may operate at amaximum inflation of 90 mbar.

Reference is now made additionally to FIGS. 7A-7D, which are simplifiedflow charts illustrating preferred modes of operation of the inflationcontrol assembly 115 of FIGS. 6A-6C. An indicated above, control of theoperation of inflation control assembly 115 is provided principally bycontroller 323 based on various sensor inputs, described hereinabove.

It is appreciated that the implementation of controller 323 may involveany suitable technology, for example, the use of embedded firmware,loading software from a digital memory device and loading software froman external source.

FIGS. 7A and 7B illustrate initialization functionality which isperformed automatically once the power switch 312 is switched to its onstate. A primary purpose of the initialization functionality is toensure that, whatever is the initial state of the control unit 117 (FIG.1A), prior to operation, balloons 108 and 127 are in their fullydeflated (vacuum) operational states.

As seen in FIGS. 7A and 7B, following powering on of the inflationcontrol assembly 115 (FIG. 1A), indication lights on panel 119 (FIG. 1A)blink, foot pedals 118 are disabled and buzzer 324 (FIGS. 6A-6C) sounds.

At this stage, initialization of one of the two identicalinflator/deflator assemblies 326 and 328 begins. Once initialization ofone of the identical inflator/deflator assemblies is completed,initialization of the other of the identical inflator/deflatorassemblies takes place. In the illustrated example, initialization ofinflator/deflator assembly 326 occurs first, starting with closing ofballoon valve 354 and opening of valve 352 thereof. After apredetermined period of time, typically 210 ms, piston 336 is positionedby motor 346 such that flange 338 is adjacent inflated balloon statussensor 344. This is the state illustrated by FIG. 6A.

The balloon valve 354 is then opened and valve 352 is closed. Followinga predetermined time duration, typically 210 ms, piston 336 is moved bymotor 346 such that flange 338 is adjacent ambient balloon status sensor342. This is the state illustrated by FIG. 6B.

Following a further predetermined time duration, typically 4 seconds,valve 352 is opened. Following an additional predetermined timeduration, typically 3 seconds, valve 352 is closed.

Following a still further predetermined time duration, typically 210 ms,piston 336 is moved by motor 346 such that flange 338 is adjacentdeflated balloon status sensor 340. This is the state illustrated byFIG. 6C.

Following yet another predetermined time duration, typically fourseconds, balloon valve 354 is closed. This completes initialization ofinflator/deflator assembly 326 and is followed by initialization ofinflator/deflator assembly 328, which includes identical steps to thosedescribed above for initialization of inflator/deflector assembly 326.

Following completion of initialization of inflator/deflator assemblies326 and 328, the indication lights on panel 119 (FIG. 1A) stop blinkingand foot pedals 118 are enabled. At this stage, two vacuum indicationlights, here designated by reference numerals 370 and 372 (FIG. 1A) areilluminated to indicate the presence of vacuum in balloons 108 and 127(FIG. 1A).

At this stage, normally inflation of one of balloons 108 and 127 takesplace. Usually, but not necessarily, inflation of balloon 108 takesplace first. As seen in FIG. 7C, inflation of balloon 108 is initiatedby an operator pressing on one of the foot pedals 118, here designatedby reference numeral 380, to send a signal to controller 323 (FIGS.6A-6C) to initiate inflation of balloon 108. Indication light 370 isextinguished and another one of the indication lights on panel 119, apressure indication light for balloon 108, here designated by referencenumeral 382 (FIG. 1A), begins blinking. Balloon valve 354 is opened.Following a predetermined time duration, typically 210 ms, piston 336 ispositioned by motor 346 such that flange 338 is adjacent inflatedballoon status sensor 344. This is the state illustrated by FIG. 6A.

At this stage, piston 336 is pressurized to a relatively high pressure,typically 200 mbar and the desired pressure at balloon 108 is typically60 mbar. Inflation of the balloon 108 is accomplished by intermittentlyopening and closing balloon valve 354 and monitoring the pressure atsensor 360, which is connected in series between piston 336 and balloon108. When the desired pressure at sensor 360 remains steady at 60 mbarfor at least a predetermined time, typically one second, balloon valve354 remains closed and inflation of balloon 108 is considered to becompleted and indicator light 382 is illuminated continuously. Evenfollowing completion of inflation of balloon 108, sensor 360 continuesto monitor the pressure and if and when necessary, balloon valve 354 maybe opened to top up the pressure at balloon 108.

Inflation of balloon 127 is initiated by an operator pressing on one ofthe foot pedals 118, here designated by reference numeral 384, to send asignal to controller 323 (FIGS. 6A-6C) to initiate inflation of balloon127. Indication light 372 is extinguished and another one of theindication lights on panel 119, a pressure indication light for balloon108, here designated by reference numeral 386 (FIG. 1A), beginsblinking. Balloon valve 354 is opened. Following a predetermined timeduration, typically 210 ms, piston 336 is positioned by motor 346 suchthat flange 338 is adjacent inflated balloon status sensor 344.

At this stage, piston 336 is pressurized to a relatively high pressure,typically 200 mbar and the desired pressure at balloon 127 is typically60 mbar. Inflation of the balloon 127 is accomplished by intermittentlyopening and closing balloon valve 354 and monitoring the pressure atsensor 360, which is connected in series between piston 336 and balloon127. When the desired pressure at sensor 360 remains steady at 60 mbarfor at least a predetermined time, typically one second, balloon valve354 remains closed and inflation of balloon 127 is considered to becompleted and indicator light 386 is illuminated continuously. Evenfollowing completion of inflation of balloon 127, sensor 360 continuesto monitor the pressure and if and when necessary, balloon valve 354 maybe opened to top up the pressure at balloon 127.

As seen in FIG. 7D, deflation of balloon 108 takes place by an operatorpressing on foot pedal 380, to send a signal to controller 323 (FIGS.6A-6C) to initiate deflation of balloon 108. Indication light 382 isextinguished and vacuum indication light 370 begins blinking. Balloonvalve 354 is closed. Following a predetermined time duration, typically210 ms, piston 336 is positioned by motor 346 such that flange 338 isadjacent ambient balloon status sensor 342 and balloon valve 354 isopened. This is the state illustrated by FIG. 6B.

At this stage, piston 336 is at approximately ambient pressure. Piston336 is then positioned by motor 346 such that flange 338 is adjacentdeflated balloon status sensor 340. This is the state illustrated byFIG. 6C.

Deflation of the balloon 108 is accomplished by monitoring the pressureat sensor 360. When the desired pressure at sensor 360 reaches anegative level of −100 mbar, balloon valve 354 is closed, deflation ofballoon 108 is considered to be completed and indicator light 370 isilluminated continuously. Even following completion of deflation ofballoon 108, sensor 360 continues to monitor the pressure inside balloon108.

Deflation of balloon 127 takes place by an operator pressing on footpedal 384, to send a signal to controller 323 (FIGS. 6A-6C) to initiatedeflation of balloon 127. Indication light 386 is extinguished andvacuum indication light 372 begins blinking. Balloon valve 354 isclosed. Following a predetermined time duration, typically 210 ms,piston 336 is positioned by motor 346 such that flange 338 is adjacentambient balloon status sensor 342 and balloon valve 354 is opened. Thisis a state corresponding to the state illustrated in FIG. 6B.

At this stage, piston 336 is at approximately ambient pressure. Piston336 is then positioned by motor 346 such that flange 338 is adjacentdeflated balloon status sensor 340.

Deflation of the balloon 127 is accomplished by monitoring the pressureat sensor 360. When the desired pressure at sensor 360 reaches anegative level of −100 mbar, balloon valve 354 is closed, deflation ofballoon 127 is considered to be completed and indicator light 372 isilluminated continuously. Even following completion of deflation ofballoon 127, sensor 360 continues to monitor the pressure inside balloon127.

One of the indicator lights on panel 119 may be a failure indicationlight, here designated by reference numeral 390. This light may beilluminated when any of the functionalities described above fails to befully performed.

Reference is now made to FIGS. 8A and 8B, which are simplified partiallycut-away illustrations of a balloon catheter 399 constructed andoperative in accordance with a preferred embodiment of the presentinvention. As seen in FIGS. 8A & 8B, the balloon catheter of the presentinvention preferably comprises an inflation tube 400 which terminates ata cap 402, which is attached at the interior of a distal end ofinflation tube 400 and preferably includes at least two lumens, heredesignated by reference numerals 404 and 406. A guide wire 410preferably extends through lumen 404 and is fixed to cap 402 thereat,while lumen 406 is open for balloon inflation and deflation.

A distal end of the guide wire 410 preferably is fixed to a tip element412, preferably within a recess 414 formed therein. A balloon 420 issealingly fixed, at a proximal end thereof, onto a distal end ofinflation tube 400 and, at a distal end thereof, onto a proximal end oftip 412.

FIG. 8A shows balloon 420 in a non-inflated, ambient state wherein thewalls of the balloon 420 are nearly taut but not appreciably tensioned.In this orientation, the guide wire 410 extends along an axis 421generally parallel to and spaced from longitudinal axis 422 of theinflation tube 400, cap 402 and tip 412. FIG. 8B shows balloon 420 in afully-inflated state, typically at a pressure of approximately 20-100millibars. It is seen that inflation of balloon 420 causes guide wire410 to be bowed in a preferably predetermined direction with respect toaxis 422, which direction is determined at least partially by thespatial relationship between axes 421 and 422, and to an extent which isa predetermined function of the amount of inflation, thus resulting in asomewhat asymmetric, off-axis, inflated balloon configuration as seen.

According to a preferred embodiment of the present invention, the lengthof balloon 420 in its non-inflated, ambient state (FIG. 8A) isapproximately 40-100 millimeters, and the length of balloon 420 in itsfully-inflated state (FIG. 8B) is approximately 30-80 millimeters. In aspecific configuration balloon 420, in its non-inflated, ambient state,has a length of 80-95 millimeters, the corresponding length of balloon420 in its fully-inflated state is 60-75 millimeters, and the diameterof balloon 420 in its fully-inflated state is 30-45 millimeters.

It is appreciated that the angle between the longitudinal axis of tipelement 412 and axis 422 in the fully-inflated state (FIG. 8B) may betypically greater than 30 degrees, and may be approximately 90 degreesor more in the specific configuration of balloon 420 describedhereabove. According to a preferred embodiment of the present invention,the angle between the longitudinal axis of the tip element 412 and axis422 in the fully-inflated state is in the range of 40-75 degrees.Alternatively, the angle between the longitudinal axis of the tipelement 412 and axis 422 in the fully-inflated state is in the range of75-110 degrees.

It is appreciated that torque may be applied to tube 400 and/or guidewire 410, thereby allowing an operator to rotate balloon 420 with tipelement 412 around axis 422 during in vivo inspection of a tubular bodyportion, such as described in one or more of applicant/assignee's PCTApplication No. PCT/IL2005/000152, filed Feb. 7, 2005; PCT ApplicationNo. PCT/IL2005/000849, filed Aug. 8, 2005, and PCT Application No.PCT/IL2007/000600, filed May 17, 2007, the disclosures of which arehereby incorporated by reference.

It is appreciated that inflation pressure in the range of 45-100millibars may be suitable for anchoring the inflated balloon 420 andthus the balloon catheter to an generally tubular body portion to beinspected or treated, such as the intestine, as described for example inone or more of applicant/assignee's PCT Application No.PCT/IL2005/000152, filed Feb. 7, 2005; PCT Application No.PCT/IL2005/000849, filed Aug. 8, 2005, and PCT Application No.PCT/IL2007/000600, filed May 17, 2007, the disclosures of which arehereby incorporated by reference.

It is appreciated that a generally higher inflation pressure may beapplied to balloon 420, as suitable. It is appreciated that guide wire410 is sufficiently flexible to allow its bending during inflation ofballoon 420 and to allow balloon 420 to be fully inflated whenappropriate inflation pressure is applied.

As seen in FIGS. 8A and 8B, inflation tube 400 protrudes into theinternal volume of balloon 420 to a certain extent. In a preferredembodiment of the present invention, tube 400 protrudes between 7 to 20millimeters into the internal volume of balloon 420. It is appreciatedthat protrusion of inflation tube 400 into the internal volume ofballoon 420 is useful for preventing or reducing blockage of inflationlumen 406 by balloon 420 in case of twisting of balloon 420 around axis422 while being inflated.

Reference is now made to FIGS. 9A, 9B, 9C, 9D, 9E and 9F, which aresimplified, partially cut away, partially sectional, illustrations ofthe operation of the apparatus of FIGS. 8A & 8B.

FIG. 9A illustrates the application of a partial vacuum, typically about−100 millibars, to the interior of balloon 420 via inflation tube 400and lumen 406 of cap 402. It is appreciated that due to the nearly taut,but not appreciably tensioned, arrangement of the balloon 420, asdescribed hereinabove with reference to FIG. 8A, the maximumcross-sectional diameter of the balloon catheter, as indicated atreference numeral 430, is relatively small, such as in the range of 2-4millimeters, and preferably less than 3 mm, and is thus suitable forpassage through an instrument channel of a conventional endoscope.

FIG. 9B illustrates the balloon catheter of FIGS. 8A-9A located in aninstrument channel 440 of a conventional endoscope 442, located withinthe intestines of a patient.

FIG. 9C illustrates the balloon catheter of FIGS. 8A-9B emerging frominstrument channel 440. FIG. 9D illustrates the balloon catheter ofFIGS. 8A-9B located at an anchoring location forward of the end of theendoscope 442. FIG. 9E illustrates the balloon catheter of FIGS. 8A-9Cfully inflated at the anchoring location. It is seen that the guide wire410 is bowed and thus the balloon 420 is generally asymmetric due to theinflation, as described above.

FIG. 9F illustrates deflation of the balloon 420 by application of apartial vacuum, typically about −100 millibars, to the interior ofballoon 420 via inflation tube 400 and lumen 406 of cap 402 andreinsertion thereof into instrument channel 440, for removal from thepatient.

Reference is now made to FIGS. 10A and 10B, which are simplified,partially cut away, partially sectional, illustrations of a ballooncatheter/external tube assembly constructed and operative in accordancewith a preferred embodiment of the present invention.

As seen in FIGS. 10A & 10B, the balloon catheter/external tube assemblyof the present invention preferably comprises an inflation tube 500which terminates at a cap 502, which is attached at the interior of adistal end of inflation tube 500 and preferably includes at least twolumens, here designated by reference numerals 504 and 506. A guide wire510 preferably extends through lumen 504 and is fixed to cap 502thereat, while lumen 506 is open for balloon inflation and deflation.

A distal end of the guide wire 510 preferably is fixed to a tip element512, preferably within a recess 514 formed therein. A balloon 520 issealingly fixed, at a proximal end thereof, onto a distal end ofinflation tube 500 and, at a distal end thereof, onto a proximal end oftip 512.

The inflation tube 500, guide wire 510 and balloon 520 are at leastpartially located within an external tube 522. External tube 522, whichmay be similar in all relevant respects to external tube 122, describedhereinabove, may be attached to an endoscope (not shown), such asendoscope 104 (FIGS. 1A & 1B), at multiple locations along its length byany suitable conventional means, such as medical adhesive tape orflexible bands (not shown).

A proximal end 524 of external tube 522 is typically open to enable aproximal end of inflation tube 500 coupled to balloon 520 to extendtherefrom outside of a patient's body, thereby enabling insertion,removal and manipulation of the balloon catheter by an operator.Additionally, any other suitable endoscope tool may be inserted, removedor manipulated through tube 522. The proximal end of inflation tube 500may be coupled to an inflation control assembly, such as inflationcontrol assembly 115 (FIGS. 1A & 1B).

A distal end 529 of external tube 522 preferably extends slidably andtelescopically through part of the length of a coil spring 530 whichmovably and slidably resides within a lumen 532, which preferably formspart of a tubular sleeve 540, which may be similar in all relevantrespects to tubular sleeve 110 (FIGS. 1A & 1B). The inflation tube 500,guide wire 510 and balloon 520 are at least partially located withinspring 530. Preferably distal end 529 is beveled for ease of passageinto and through coil spring 530. It is a particular feature of thepresent invention that spring 530 defines a generally non-collapsibleand highly flexible channel for the balloon catheter.

FIG. 10A shows balloon 520 in a non-inflated, ambient state interior ofspring 530 wherein the walls of the balloon 520 are nearly taut but notappreciably tensioned. In this orientation, the guide wire 510 and tip512 extend along an axis parallel to and spaced from longitudinal axis542 of the inflation tube 500 and cap 502. FIG. 10B shows balloon 520 ina fully-inflated state forward of the external tube 522 and of spring530, typically at a pressure of approximately 20-100 millibars. It isseen that inflation of balloon 520 causes guide wire 510 to be bowed ina predetermined direction with respect to axis 542, and to an extentwhich is a predetermined function of the amount of inflation, thusresulting in a somewhat asymmetric, off-axis, inflated balloonconfiguration as seen.

According to a preferred embodiment of the present invention, the lengthof balloon 520 in its non-inflated, ambient state (FIG. 10A) isapproximately 40-100 millimeters, and the length of balloon 520 in itsfully-inflated state (FIG. 10B) is approximately 30-80 millimeters. In aspecific configuration balloon 520, in its non-inflated, ambient state,has a length of 80-95 millimeters, the corresponding length of balloon520 in its fully-inflated state is 60-75 millimeters, and the diameterof balloon 520 in its fully-inflated state is 30-45 millimeters.

It is appreciated that the angle between the longitudinal axis of tipelement 512 and axis 542 in the fully-inflated state (FIG. 10B) may betypically greater than 30 degrees, and may be approximately 90 degreesor more in the specific configuration of balloon 520 describedhereinabove. According to a preferred embodiment of the presentinvention, the angle between the longitudinal axis of the tip element512 and axis 542 in the fully-inflated state is in the range of 40-75degrees. Alternatively, the angle between the longitudinal axis of thetip element 512 and axis 542 in the fully-inflated state is in the rangeof 75-110 degrees.

It is appreciated that torque may be applied to tube 500 and/or guidewire 510, thereby allowing an operator to rotate balloon 520 with tipelement 512 around axis 542 during in vivo inspection of a tubular bodyportion, such as described in one or more of applicant/assignee's PCTApplication No. PCT/IL2005/000152, filed Feb. 7, 2005; PCT ApplicationNo. PCT/IL2005/000849, filed Aug. 8, 2005, and PCT Application No.PCT/IL2007/000600, filed May 17, 2007, the disclosures of which arehereby incorporated by reference.

It is appreciated that inflation pressure in the range of 45-100millibars may be suitable for anchoring the inflated balloon 520 andthus the balloon catheter to an generally tubular body portion to beinspected or treated, such as the intestine, as described for example inone or more of applicant/assignee's PCT Application No.PCT/IL2005/000152, filed Feb. 7, 2005; PCT Application No.PCT/IL2005/000849, filed Aug. 8, 2005, and PCT Application No.PCT/IL2007/000600, filed May 17, 2007, the disclosures of which arehereby incorporated by reference.

It is appreciated that a generally higher inflation pressure may beapplied to balloon 520, as suitable. It is appreciated that guide wire510 is sufficiently flexible to allow its bending during inflation ofballoon 520 and to allow balloon 520 to be fully inflated whenappropriate inflation pressure is applied.

As seen in FIGS. 10A and 10B, inflation tube 500 protrudes into theinternal volume of balloon 520 to a certain extent. In a preferredembodiment of the present invention, tube 500 protrudes between 7 to 20millimeters into the internal volume of balloon 520. It is appreciatedthat protrusion of inflation tube 500 into the internal volume ofballoon 520 is useful for preventing or reducing blockage of inflationlumen 506 by balloon 520 in case of twisting of balloon 520 around axis542 while being inflated.

Reference is now made to FIGS. 11A, 11B, 11C, 11D, 11E and 11F, whichare simplified, partially cut away, partially sectional, illustrationsof the operation of the apparatus of FIGS. 10A & 10B.

FIG. 11A illustrates the application of a partial vacuum, typicallyabout −100 millibars, to the interior of balloon 520 via inflation tube500 and lumen 506 of cap 502. It is appreciated that due to the nearlytaut, but not appreciably tensioned, arrangement of the balloon 520, asdescribed hereinabove with reference to FIG. 10A, the maximumcross-sectional diameter of the balloon catheter, as indicated atreference numeral 544, is relatively small, such as in the range of 2-4millimeters, and preferably less than 3 mm, and is thus suitable forpassage through the external tube 522 when coupled to a conventionalendoscope 550.

FIG. 11B illustrates the balloon catheter of FIGS. 10A-11A locatedinside spring 530 interiorly of tubular sleeve 540, forward of externaltithe 522, located within the intestines of a patient.

FIG. 11C illustrates the balloon catheter of FIGS. 10A-11B emerging fromspring 530. FIG. 11D illustrates the balloon catheter of FIGS. 10A-11Clocated at an anchoring location forward of the end of the tubularsleeve 540. FIG. 11E illustrates the balloon catheter of FIGS. 10A-11Dfully inflated at the anchoring location. It is seen that the guide wire510 is bowed and thus the balloon 520 is generally asymmetric due to theinflation, as described above.

FIG. 11F illustrates deflation of the balloon 520 by application of apartial vacuum, typically about −100 millibars, to the interior ofballoon 520 via inflation tube 500 and lumen 506 of cap 502 andreinsertion thereof into spring 530, for removal from the patient or asneeded during a procedure, for example for allowing better opticalviewing of an organ during endoscopy.

Reference is now made to FIG. 12, which is a simplified illustration ofa flexible endoscope system similar to that shown in FIGS. 1A and 1B.The embodiment of FIG. 12 is identical to that described hereinabovewith reference to FIGS. 1A and 1B with the addition of a fluidcommunication port 610, preferably a 3-port connector in which two ofthe three ports are arranged in line with the external tube 122, forproviding fluid communication with the interior of external tube 122.The embodiment of FIG. 12 also includes a drainage vessel 620,associated with external tube 122 for receiving liquid, such as bodyfluids, from the interior of external tube 122.

FIG. 13A illustrates fluid communication port 610 arranged in line withexternal tube 122 and coupled to a fluid container, line or reservoir630, which may be, for example, a syringe, a source of gas underpositive pressure, a vacuum source or a drainage vessel.

In accordance with a preferred embodiment of the present invention, anouter surface of inflation tube 126, shown interiorly of external tube122 and of port 610, may be coated with a hydrophilic coating. Acommercially available, hydrophilic coated, inflation tube 126 is aSlipskin™ coated PVC tube, available from MCTec of 9 Edisonstraat,Venlo, Netherlands. If water or a water-soluble material is injectedinto the external tube 122 outside of inflation tube 126, passage ofinflation tube 126 through external tube 122 is greatly facilitated by aresulting reduction in friction.

FIG. 13B illustrates drainage vessel 620 coupled in-line with externaltube 122 and configured as a cylinder which is coaxial with externaltube 122 to allow collection of drainage liquid irrespective of theorientation of the external tube 122.

Reference is now made to FIGS. 14A, 14B, 14C & 14D, which aresimplified, partially cut away, partially sectional, illustrations ofthe operation of an endoscope tool 128 as shown and describedhereinabove with reference to FIGS. 2A-3B, including a balloon catheter399 as shown and described hereinabove with reference to FIGS. 8A & 8B,extending through an instrument channel 440 of an endoscope 442, such asthat shown and described hereinabove with reference to FIGS. 9B-9F, in aspecific context, the junction between the colon and the small intestineat the ileo-cecal valve, designated by reference numeral 650.

FIGS. 14A and 14B together show bending of endoscope tool 128, locatedin the colon, such that distal portion 178 and tip element 170 aredirected through ileo-cecal valve 650. FIG. 14C shows anchoring of theballoon catheter 399 in the small intestine by inflation of balloon 420,causing bowing of guide wire 410. FIG. 14D shows forward displacement ofendoscope 442 along endoscope tool 128 through the ileo-cecal valve 650.

Reference is now made to FIGS. 15A and 15B, which are respectiveexploded and partially cut-away pictorial illustrations of a catheter orendoscope tool and associated inflation tube, constructed and operativein accordance with another preferred embodiment of the presentinvention.

As seen in FIGS. 15A & 15B, an inflation tube 726 preferably includes atleast two lumens, here designated by reference numerals 728 and 730. Aselectable steering wire 732 preferably extends through lumen 728. Lumen730 is a balloon inflation lumen and extends through a relatively narrowdistal portion 734 of the inflation tube which extends forward of distalend of lumen 728 and communicates with a balloon inflation port 736.

A collar 740 preferably fixedly attaches a distal end of selectablesteering wire 732 to the distal portion 734 forwardly of at least oneindentation 742. In this embodiment, the attachment location, designatedby reference numeral 744, of the distal end of the selectable steeringwire 732 to the distal portion 734 of the inflation tube 726 by collar740 lies within a balloon 750.

A distal end of the distal portion 734 of the inflation tube 726preferably is fixed to a tip element 752, preferably within a recess 754formed therein. Balloon 750 is sealingly fixed, at a proximal endthereof, onto a distal end of inflation tube 726 and, at a distal endthereof, onto a proximal end of tip element 752.

Reference is now made to FIGS. 16A & 16B, which are sectionalillustrations of the catheter or endoscope tool of FIGS. 15A & 15B inrespective straight and bent operative steering orientations. FIG. 16Ashows the catheter or endoscope tool extending along a longitudinal axis760. In FIG. 16B, it is seen that when selectable steering wire 732 isretracted relative to inflation tube 726, as indicated by arrow 762, itapplies a pulling force to a forward part of the distal portion 734lying forwardly of at least one indentation 742, causing that forwardpart of distal portion 734 and tip element 752 to rotate in a directionindicated by arrow 770 relative to longitudinal axis 760. Preferably thedistal portion 734 is sufficiently resilient under such bending so as toreturn to its axial orientation shown in FIG. 16A once selectablesteering wire 732 is released.

It is appreciated that torque may be applied to inflation tube 726,thereby allowing an operator to rotate balloon 750 with tip element 752around axis 760 during in vivo inspection of a tubular body portion,such as described in one or more of applicant/assignee's PCT ApplicationNo. PCT/IL2005/000152, filed Feb. 7, 2005; PCT Application No.PCT/IL2005/000849, filed Aug. 8, 2005, and PCT Application No.PCT/IL2007/000600, filed May 17, 2007, the disclosures of which arehereby incorporated by reference.

Reference is now made to FIGS. 17A and 17B, which are simplifiedillustrations of a portion of an alternative embodiment of the flexibleendoscope system of FIGS. 1A and 1B, in respective deflated and inflatedoperative orientation at an anchoring location in the small intestine.As seen, a peripheral balloon 800 surrounds a tubular sleeve 802, whichmay be similar in all relevant respects to tubular sleeve 110 (FIGS. 1A& 1B).

Preferably, peripheral balloon 800 includes a forward facing portion 810and a rearward facing portion 812, separated by a central portion 814.It is a particular feature of the present invention that both theforward facing portion 810 and the rearward facing portion 812 aretapered, both when deflated, as seen in FIG. 17A, and when inflated, asseen in FIG. 17B. It is a further particular feature of the presentinvention that the slope of the forward facing portion 810 is differentthan, greater than and opposite to that of rearward facing portion 812.

According to a preferred embodiment of the present invention, the slopeof rearward facing portion 812, when inflated, is greater than 45degrees and more preferably greater than 60 degrees, and the slope ofthe forward facing portion 810, when inflated, is less than 60 degreesand more preferably less than 45 degrees.

In a specific embodiment of the present invention, the slope of theforward facing portion 810 is approximately 45 degrees and the slope ofthe rearward facing portion 812 is approximately 60 degrees. This isparticularly helpful during an endoscopy procedure, as described forexample in one or more of applicant/assignee's PCT Application No.PCT/IL2005/000152, filed Feb. 7, 2005; PCT Application No.PCT/IL2005/000849, filed Aug. 8, 2005, and PCT Application No.PCT/IL2007/000600, filed May 17, 2007, the disclosures of which arehereby incorporated by reference.

For example, a small slope of forward facing portion 810 when theballoon 800 is not fully inflated may allow more efficient and lowerfriction advancement of an endoscope assembly for in vivo inspection ofa generally tubular body portion such as an intestine, as described forexample in one or more of applicant/assignee's PCT Application No.PCT/IL2005/000152, filed Feb. 7, 2005; PCT Application No.PCT/IL2005/000849, filed Aug. 8, 2005, and PCT Application No.PCT/IL2007/000600, filed May 17, 2007, the disclosures of which arehereby incorporated by reference.

A high slope of rearward facing portion 812, for example, may prevent orminimize slippage and undesired withdrawal of an endoscope assemblyduring in vivo inspection of a generally tubular body portion such as anintestine, as described for example in one or more ofapplicant/assignee's PCT Application No. PCT/IL2005/000152, filed Feb.7, 2005; PCT Application No. PCT/IL2005/000849, filed Aug. 8, 2005, andPCT Application No. PCT/IL2007/000600, filed May 17, 2007, thedisclosures of which are hereby incorporated by reference.

It will be appreciated by persons skilled in the art that the presentinvention is not limited by what has been particularly shown anddescribed herein above.

Rather the scope of the present invention includes both combinations andsubcombinations of the various features described hereinabove as well asvariations and modifications which would occur to persons skilled in theart upon reading the specifications and which are not in the prior art.

What is claimed is:
 1. An endoscope system comprising: an endoscope; anexternal tube associated with said endoscope and extending alongsidesaid endoscope; an endoscope tool extending through said external tubeand having formed along at least part of an elongate surface thereof ahydrophilic coating; and a liquid communication port associated withsaid external tube for providing liquid communication with the interiorof said external tube.
 2. The endoscope system of claim 1 and furthercomprising a drainage vessel associated with said external tube forreceiving liquid from the interior of said external tube.
 3. An externaltube assembly configured for use with an endoscope, the external tubeassembly comprising: an external tube associated with said endoscope andextending alongside said endoscope; an endoscope tool extending throughsaid external tube and having formed along at least part of an elongatesurface thereof a hydrophilic coating; and a liquid communication portassociated with said external tube for providing liquid communicationwith the interior of said external tube.
 4. The external tube assemblyof claim 3 and further comprising a drainage vessel associated with saidexternal tube for receiving liquid from the interior of said externaltube.